Stereodivergent Synthesis of Tertiary Fluoride-Tethered Allenes via Copper and Palladium Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(19), P. 7285 - 7291

Published: May 10, 2021

Herein we describe a protocol for the unprecedented stereodivergent synthesis of tertiary fluoride-tethered allenes bearing stereogenic center and axis via Cu/Pd synergistic catalysis. A broad scope conjugated enynes are coupled with various α-fluoroesters in high yields diastereoselectivities generally >99% ee. In addition, four stereoisomers allene products ensure precise access to corresponding fluorinated hydrofurans novel axial-to-central chirality transfer process.

Language: Английский

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Radical transformations for allene synthesis

Chemical Science, Journal Year: 2022, Volume and Issue: 13(29), P. 8491 - 8506

Published: Jan. 1, 2022

Allenes are valuable organic molecules that feature unique physical and chemical properties. They not only often found in natural products, but also act as versatile building blocks for the access of complex molecular targets, such pharmaceuticals, functional materials. Therefore, many remarkable elegant methodologies have been established synthesis allenes. Recently, more methods radical allenes developed, clearly emphasizing associated great synthetic values. In this perspective, we will discuss recent important advances

Language: Английский

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Copper-Catalyzed Asymmetric Yne-Allylic Substitution Using Electron-Rich Arenes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(4), P. 2746 - 2757

Published: Feb. 7, 2024

Remote stereocontrol in transition-metal catalysis is a challenging but interesting research topic. In this work, we achieved copper-catalyzed asymmetric yne-allylic substitution using electron-rich arenes and acyclic carbonates through remote enantioselectivity control. The reaction delivers variety of enantioenriched products that contain diverse set valuable moieties, such as conjugated enynes, indoles, indolizines, allenes, dihydrofurans, which are widely used organic synthesis act key units bioactive molecules natural products. synthetic value protocol has been demonstrated series further transformations, mechanistic studies have conducted to gain more insight into the reaction.

Language: Английский

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1,4-Alkylcarbonylation of 1,3-Enynes to Access Tetra-Substituted Allenyl Ketones via an NHC-Catalyzed Radical Relay

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(21), P. 13363 - 13373

Published: Oct. 19, 2021

Reactions involving allenyl ion intermediates have been widely applied in the synthesis of functionalized allenes, but reactions radicals less studied and limited successful examples realized mainly by transition metal catalysis. We herein demonstrate generation N-heterocyclic carbene (NHC) organocatalysis their applications three-component radical relay 1,4-alkylcarbonylation 1,3-enynes without participation. This strategy could accommodate a collection different alkyl precursors such as CF3I, halides, cycloketone oxime esters, aliphatic carboxylic acid derived redox-active enabling convenient pathway to access range synthetically challenging tetra-substituted ketones with high regioselectivity. The key success this protocol relied on Csp-C(O)sp2 radical–radical coupling NHC-bound ketyl radicals, constructing ketone motifs highly efficient reaction pathway.

Language: Английский

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Regiodivergent sulfonylarylation of 1,3-enynes via nickel/photoredox dual catalysis

Chemical Science, Journal Year: 2021, Volume and Issue: 12(40), P. 13564 - 13571

Published: Jan. 1, 2021

Catalytic difunctionalization of 1,3-enynes represents an efficient and versatile approach to rapidly assemble multifunctional propargylic compounds, allenes 1,3-dienes. Controlling selectivity in such addition reactions has been a long-standing challenging task due multiple reactive centers resulting from the conjugated structure 1,3-enynes. Herein, we present straightforward method for regiodivergent sulfonylarylation via dual nickel photoredox catalysis. Hinging on nature 1,3-enynes, diverse reaction pathways are feasible: synthesis α-allenyl sulfones 1,4-sulfonylarylation, or preparation (E)-1,3-dienyl with high chemo-, regio- stereoselectivity through 3,4-sulfonylarylation. Notably, this is first example that catalysis merged achieve

Language: Английский

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Decarboxylative 1,4-carbocyanation of 1,3-enynes to access tetra-substituted allenes via copper/photoredox dual catalysis

Chemical Science, Journal Year: 2021, Volume and Issue: 12(34), P. 11316 - 11321

Published: Jan. 1, 2021

We disclose herein the first example of merging photoredox catalysis and copper for radical 1,4-carbocyanations 1,3-enynes. Alkyl N-hydroxyphthalimide esters are utilized as precursors, reported mild redox-neutral protocol has broad substrate scope remarkable functional group tolerance. This strategy allows synthesis diverse multi-substituted allenes with high chemo- regio-selectivities, also permitting late stage allenylation natural products drug molecules.

Language: Английский

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Asymmetric 1,4-functionalization of 1,3-enynes via dual photoredox and chromium catalysis

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Aug. 26, 2022

Abstract The merger of photoredox and transition-metal catalysis has evolved as a robust platform in organic synthesis over the past decade. stereoselective 1,4-functionalization 1,3-enynes, prevalent synthon synthetic chemistry, could afford valuable chiral allene derivatives. However, tremendous efforts have been focused on ionic reaction pathway. radical-involved asymmetric 1,3-enynes remains prominent challenge. Herein, we describe three-component 1,4-dialkylation via dual chromium to provide allenols. This method features readily available starting materials, broad substrate scope, good functional group compatibility, high regioselectivity, simultaneous control axial central chiralities. Mechanistic studies suggest that this proceeds through redox-neutral

Language: Английский

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Palladium-Catalyzed Asymmetric Sequential Hydroamination of 1,3-Enynes: Enantioselective Syntheses of Chiral Imidazolidinones

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(25), P. 11364 - 11376

Published: June 10, 2022

Pd-catalyzed sequential hydroamination of readily available 1,3-enynes is reported. The redox-neutral process provides an efficient route to synthesize a broad scope imidazolidinones, thiadiazolidines, and imidazolidines. Asymmetric generates series synthetically valuable, enantioenriched imidazolidinones. Mechanistic studies revealed that the transformation occurred via intermolecular enyne pathway give allene intermediate. Subsequent intramolecular intermediate proceeded under Curtin-Hammett principle provide imidazolidinone products.

Language: Английский

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Modular Synthesis of Multifunctionalized CF₃-Allenes through Selective Activation of Saturated Hydrocarbons

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(16), P. 10207 - 10221

Published: Aug. 5, 2022

Catalytic 1,4-dicarbofunctionalization of 1,3-enynes is a powerful strategy for the synthesis polysubstituted allenes. Despite impressive progress, such still restricted to use alkyl-metallic reagents or pre-activated radical precursors, thus limiting its functional group compatibility and atom economy. Herein, we report that through combination decatungstate photo-hydrogen transfer nickel catalysis, three-component 2-trifluoromethyl-1,3-enynes achieved. This allows modular tetrasubstituted CF3-allenes under exceptionally mild conditions. A variety electrophiles as aryl bromides, alkenyl acyl chlorides, alkynyl bromides were successfully employed traps lead desired products. Another significant advantage most abundant hydrocarbons are used feedstocks, wide range synthetically versatile groups complex drug-like structures can be easily incorporated. Based on experimental density theories, possible catalytic cycle involving 1,3-nickel rearrangement proposed.

Language: Английский

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Radical Acylalkylation of 1,3-Enynes To Access Allenic Ketones via N-Heterocyclic Carbene Organocatalysis

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(8), P. 5229 - 5241

Published: March 29, 2022

An N-heterocyclic carbene organocatalytic 1,4-difunctionalization of 1,3-enynes was developed. This strategy suitable for a broad spectrum substrates to efficiently synthesize allenic ketones bearing diverse substituents. Preliminary mechanistic studies suggest radical reaction pathway this acylalkylation process.

Language: Английский

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